摘要:
Apparatus, and an associated method, for facilitating selection of link parameters associated with a communication signal transmitted in a radio communication system, such as a GSM (global system for mobile communications) system which provides for GPRS (general packet radio service). Uplink sounding bursts are generated by a mobile station and transmitted to the network infrastructure of the radio communication system. The uplink sounding bursts are analyzed to determine channel conditions upon which the uplink sounding bursts are transmitted. Responsive thereto, selection is made of one or more link parameters of which subsequently-generated GPRS, or other, messages to be transmitted by the mobile station are to be formed. Indications of the selection are provided to the mobile station to permit formation of the subsequently-generated messages in manners which conform with the selected link parameter.
摘要:
A method for transmitting a communication signal (20) having a data rate over a plurality of spread spectrum traffic channels includes determining a first number of traffic channels required to transmit the communication signal at the data rate, and determining a second number of traffic channels (502) available for transmitting the communication signal (20). In response to a comparison of the first number of traffic channels to the second number of traffic channels, a first traffic channel (54) for transmitting a first portion of the communication signal (50, 51) and a second traffic channel (56) for transmitting a second portion of the communication signal (52, 53) are selected from the. second number of traffic channels (502). The selection of the first traffic channel (54) is non deterministic of the selection of the second traffic channel (56).
摘要:
Power control in a spread spectrum communication system takes place by determining a speed of a remote unit (405) and assigning as a power-control threshold a target threshold based on the determined speed (410). An instantaneous threshold value is created (415) based on frame-quality information and the target threshold. An energy of a power-control group transmitted (430) from a remote unit is compared to the instantaneous threshold value and a power-adjustment command is determined. The power-adjustment command is transmitted to the remote unit instructing the remote unit to adjust its power accordingly.
摘要:
A receiver (200, 400) implements improved channel estimation. The receiver (200, 400) demodulates a transmitted signal, and makes an initial channel estimate (115). The receiver (200, 400) then makes a hard decision (301) as to whether the channel estimate was correct and groups samples representing the decision. A vector sum of the group of samples is computed (302), and each sample is compared to the vector sum (303). The sample having the largest projection on the vector sum is retained (304), and the other samples are considered noise, and are thus discarded (305). After obtaining a predetermined number of retained samples (306), the retained samples are used to generate an new channel estimate (226). Since the noisy estimates are discarded, the new channel estimate (226) contains fewer errors than the initial channel estimate (115). The new channel estimate (226) is used to generate decoded data (250).
摘要:
A method and device for estimating a target chip index value in a code-division multiple access receiver. The receiver receives signals from a transmitter that uses a plurality of transmitted chips for data transmission through a plurality of multipath channels. As each channel is expressible as a channel impulse response at a given instant in time, the impulse response can be sampled and the samples indexed by a plurality of delay sample indices. The target chip index value can be determined based on the first moment of the delay sample indices over an impulse response.
摘要:
In a communication system where a continuous reverse channel transmission is utilized by redundant transmission of Walsh codes, a current transmission rate is modulated onto Walsh code polarity. In particular, a remote unit operating at a particular transmission rate utilizing a continuous reverse channel transmission modulates the transmission rate by setting the polarity of each Walsh code depending upon the current or future data traffic channel rate. In communication systems where a Reference Coherent (RC) type transmission is utilized, the particular transmission rate is modulated onto the reference symbols (501-517) by setting the reference symbols (501-517) equal to a binary "1" or "0".
摘要:
A method and apparatus is provided for facilitating coherent communication reception. A received reference symbol coded spread spectrum communication signal is despread with a spreading code to derive a stream of reference samples and a stream of data samples. The channel response is estimated by utilizing the stream of reference samples. An offset frequency detector determines an offset to be applied to the received signal via a frequency locked loop, while a timing control compensates for slow timing drift and fast fading based on power estimates derived from the stream of reference samples and/or the stream of data samples. A rate estimator determines the rate at which the information was encoded, and the rate information is used to optimize the timing control, frequency offset detector and channel estimator. Thus an improved detection of estimated data symbols from the stream of received data samples is provided.
摘要:
A method and apparatus provide a systolic equalizer for Viterbi equalization of an 8-PSK signal distorted by passage through a communication channel. The systolic equalizer architecture is scalable to process, as examples, four, eight and 16 state received signals. An equalizer in accordance with this invention includes a logical arrangement of a plurality of instantiations of locally coupled processing elements forming a systolic array for processing in common received signal samples having distortion induced by passage through a communication channel. The equalizer outputs soft values for input to a decoder, the soft values representing an approximation of maximum a posteriori (MAP) probabilities. A trellis search procedure is employed to reconstruct estimates of a received signal sequence based on a reduced number of states. The reduced number of states is represented by a plurality of groups determined by partitioning a symbol constellation such that there are fewer groups than possible symbols.
摘要:
Apparatus, and an associated method, for a radio, such as cellular, communication system to facilitate communications between a mobile station and the network infrastructure. When the mobile station registers in the communication system, a dedicated reverse-link channel is allocated to facilitate communications of packet data between the mobile station and the network infrastructure. By providing dedicated channels, the mobile station becomes functionally connected to the network infrastructure and are analogous to a hard wired connection of a computer in a local area network.
摘要:
The method includes acquiring a signal (501); inputting (502), at a first time, a received symbol to a demodulator having a plurality of outputs to produce a set of early outputs; inputting (504), at a second time, the received symbol to the demodulator to produce a set of on-time outputs; inputting (505), at a third time, the received symbol to the demodulator to produce a set of late outputs; and comparing (506) at least one output in the set of early outputs with at least one output in the set of late outputs to produce a timing measure.